CN117301761B - Bicycle wheel with improved rim - Google Patents
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- CN117301761B CN117301761B CN202311444336.2A CN202311444336A CN117301761B CN 117301761 B CN117301761 B CN 117301761B CN 202311444336 A CN202311444336 A CN 202311444336A CN 117301761 B CN117301761 B CN 117301761B
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Abstract
The application relates to the technical field of vehicle accessories, in particular to a bicycle wheel with an improved rim. Including wheel rim, wheel tire, wheel hub and wheel spoke, be equipped with the wheel tire on the wheel rim, the center of wheel rim is provided with wheel hub, wheel hub is connected with the wheel rim through a plurality of wheel spokes, the wheel rim be ring shape, the wheel rim includes rim groove and rim wall, the rim wall is the symmetry form setting, is provided with the rim groove between the rim wall, be provided with the drag reduction generator more than one set of on the lateral surface of rim wall, the drag reduction generator is the spiral, and is array form setting on the circumference of rim wall. The application has the advantages of reduced production cost, improved wheel performance, good drag reduction effect, easy adjustment of functional scenes and low research and development cost, solves the problems of high production cost, lack of performance improvement, poor drag reduction effect and single functional surface existing in the existing bicycle wheels, and meets the use requirement of the bicycle.
Description
Technical Field
The invention relates to the technical field of vehicle accessories, in particular to a bicycle wheel with an improved rim.
Background
The basic technology of bicycle wheels has evolved in recent years, with the aim of designing bicycle wheels designed for racing purposes, which are increasingly aimed at being lightweight and having good aerodynamic efficiency.
In order to reduce the weight of bicycle wheels, carbon fiber composites are widely used in the manufacture of bicycle wheel rims. By using carbon fiber composite materials, the rim of a bicycle wheel can be more freely shaped, thereby achieving performance advantages of different orientations.
On the other hand, the aerodynamic efficiency of bicycle wheel rims is also one of the most important technical improvements. To achieve this result, a variety of different rim shapes have been produced, most of which are designed to better control the air flow over the rim to reduce the aerodynamic drag of the wheel.
One form of such rim shape that improves the aerodynamic efficiency of a bicycle wheel rim is to increase the radial extent of the side surfaces of the rim, producing a "deep section" rim. By comparison, the side surface of a typical spoke wheel rim extends radially about 25mm or less. In contrast, the radial extension of a deep section rim may exceed 30mm, typically 50mm or more. This improvement does not generally increase the cost and difficulty of production of the rim, but it does significantly increase the weight, impact the driving and acceleration properties.
Another technique for improving the aerodynamic efficiency of a wheel rim involves the placement of specific surface textures on the rim-side surface, which are designed to reduce turbulence generated by the wheel when it is travelling in air, and thus reduce aerodynamic drag on the wheel. The improvement does not increase the weight significantly, but increases the complexity of production significantly, reduces the production efficiency and yields.
Although the above-described technique provides a significant improvement in aerodynamic efficiency of bicycle wheel rims, there are still more aerodynamic efficient solutions as part of the technological innovation in the racing bicycle industry.
Disclosure of Invention
The object of the present invention is to provide a form of rim which is capable of improving the aerodynamic efficiency of the rim more effectively than the way in which the radial extent of the rim-side surface is increased, and in which a specific surface texture is arranged on the rim-side surface, and at the same time, which does not significantly increase the production cost and difficulty of production of the rim nor the weight, so that there are one or both of the advantages of better drag reduction effect, lower production cost, and lighter weight than the above-mentioned improvement.
In order to solve the problems, the invention is realized according to the following technical scheme:
The invention relates to a bicycle wheel with an improved rim, which comprises a wheel rim, a wheel tire, a wheel hub and wheel spokes, wherein the wheel tire is arranged on the wheel rim, the wheel hub is arranged in the center of the wheel rim, the wheel hub is connected with the wheel rim through a plurality of wheel spokes, the wheel rim is in a circular ring shape, the wheel rim comprises rim grooves and rim walls, the rim walls are symmetrically arranged, the rim grooves are arranged between the rim walls, more than one group of drag reduction generators are arranged on the outer side surface of the rim walls and used for increasing the attachment capacity of air flow and reducing air resistance, and the drag reduction generators are in a spiral shape and are arranged in an array shape in the circumferential direction of the rim walls; the drag reduction generator and the rim wall are integrally formed, the drag reduction generator comprises a convex part and a concave part, and continuous smooth transition is arranged between the convex part and the concave part; the number of the drag reduction generators is 16-18 groups; the surfaces of the convex part and the concave part are in cosine function curve shapes;
Wherein an initial wheel rim section is generated in which a side surface of a rim wall is engaged with air during running, a boundary curve of the rim wall is obtained, a start point and an end point of the boundary curve are connected by a smooth curve, the boundary curve and the smooth curve are collectively referred to as a curve C0, the start point of the boundary curve is taken as a first point PNT 0-0, the curve C0 is uniformly divided into n equal divisions to obtain n intersecting points PNT 0-1～PNT0-n,
The curve C0 is shifted outward by a distance to obtain a curve C0', the reference point PNT 0'-0～PNT0'-n is also taken,
The curve C0 is shifted inward by a distance to obtain a curve C0", likewise taking the reference point PNT 0"-0～PNT0"-n,
The reference points are connected in a PNT0-0-PNT0'-1-PNT0-2-PNT0"-3-PNT0-4…PNT0-n-PNT0'-(n+1)-PNT0-(n+2)-PNT0"-(n+3)-PNT0-(n+4) cyclic manner to obtain a curve W0,
The reference plane is rotated around the central axis of the hub by an angle, curves C1, C1 'and C1' are established in the same way, a point set PNT 1-0～PNT1-n、PNT1'-0～PNT1'-n、PNT1"-0～PNT1"-n is obtained in the same way, reference points are connected in a cyclic way of PNT1"-0-PNT1-1-PNT1'-2-PNT1-3-PNT1"-4…PNT1"-n-PNT1-(n+1)-PNT1'-(n+2)-PNT1-(n+3)-PNT1"-(n+4) to obtain a curve W1, a plurality of curves W0-Wn are obtained in the same way, the curves are connected as contour lines to form a curved surface, wherein the reference point PNT 0-0 of the curve W0 is connected with the reference point PNT 1-1 of the curve W1, the reference point PNT 2_2 of the curve W2, the reference point PNT 3_3 … of the curve W3 is connected with the reference point PNT n-n of the curve Wn, the reference point PNT 0'-1 of the curve W0 is connected with the reference point PNT 1'-2 of the curve W1, the reference point PNT 2'-3 … of the curve W2 is connected with the reference point PNT n'-(n+1) of the curve Wn in a one-to-one correspondence manner, and a curved surface shape is obtained, and the curved surface shape is displayed in a convex shape and a concave shape extending towards the outer edge.
The drag reduction generators (104) are arranged periodically, wherein the axial heights of the drag reduction generators are equal, or the axial heights of the drag reduction generators are equal.
The height difference between the convex part and the concave part is 0.5-2 mm.
The rim wall has a ring width of not less than 30 mm.
The rim groove is U-shaped, and a plurality of spoke connecting holes are formed in the bottom of the rim groove.
Compared with the prior art, the invention has the beneficial effects that:
The application provides the bicycle wheel with the improved rim, which has the advantages of reducing production cost, improving wheel performance, having good resistance reducing effect, being easy to adjust functional scenes and having low research and development cost, adopting a special wheel rim resistance reducing structure to realize the purpose of resistance reduction under the condition of not changing new materials, saving the material cost of the new materials.
In addition, the drag reduction generator of the wheel rim can realize the purposes of changing the overall weight, balancing the production difficulty and adjusting the drag reduction effect by adjusting the height or changing the height difference of the protruding part and the recessed part, and can rapidly test the product type meeting the scene function requirement through the aerodynamic simulation parameter effect of a computer.
Drawings
The invention is described in further detail below with reference to the attached drawing figures, wherein:
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is a schematic structural view of the wheel rim of the present invention;
FIG. 3 is a schematic cross-sectional view of a wheel rim of the present invention;
FIG. 4 is a schematic cross-sectional view of a drag reducing generator of the present invention;
FIG. 5 is a schematic air flow diagram of the wheel rim of the present invention;
FIG. 6 is a schematic illustration of one of the crosswind flows of the wheel rim of the present invention;
FIG. 7 is a schematic illustration of the side air flow of a wheel rim of the present invention;
FIG. 8 is a schematic air flow diagram of the improved wheel rim of the present invention;
FIG. 9 is one of the boundary curve subdivision schemes of the present invention;
FIG. 10 is a schematic diagram of a subdivision of the boundary curve according to the present invention;
FIG. 11 is a schematic diagram of a subdivision of the boundary curve of the present invention;
FIG. 12 is a schematic view of a surface fit of a boundary curve of the present invention;
FIG. 13 is a schematic view of a surface fit of a boundary curve according to the present invention;
FIG. 14 is one of the aerodynamic schematics of the present invention;
FIG. 15 is a second aerodynamic schematic of the present invention;
fig. 16 is a third aerodynamic schematic of the present invention.
In the figure: 1. wheel rims 102, rim wells 103, rim walls 104, drag reducing generators 105, protrusions 106, depressions 107, spoke attachment holes,
2. Tyre for vehicle wheels, 3, wheel hub, 4, wheel spoke.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be described in further detail below with reference to the accompanying drawings, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
As shown in fig. 1, the bicycle wheel with the improved rim according to the present invention comprises a wheel rim 1, a wheel tire 2, a wheel hub 3 and wheel spokes 4, wherein the wheel tire 2 is mounted on the wheel rim 1, the wheel rim 1 is used for supporting the wheel tire 2 so as to keep a normal shape and contact with the ground, and the wheel rim 1 has certain strength and rigidity so as to bear external forces such as impact, pressure and rotation from the ground. The center of wheel rim 1 is provided with wheel hub 3, and wheel hub 3 is connected with wheel rim 1 through a plurality of wheel spokes 4, and wheel spoke 4 plays the effect of supporting and transmission strength, and optionally, wheel spoke 4 is made by the stainless steel, has better bendability and intensity, and wheel spoke 4 transmits the force on the wheel hub 3 to wheel rim 1 through self tension, guarantees the stability and the intensity of bicycle wheel.
Further, the wheel rim 1 is in a circular ring shape, the wheel rim 1 comprises a rim groove 102 and a rim wall 103, the rim wall 103 is symmetrically arranged, the width of the ring width of the rim wall 103 is not less than 30 mm, and as a preferred embodiment of the application, the width of the ring width of the rim wall 103 is 50 mm, the arrangement has the advantages that the side surface area of the rim wall 103 is enlarged, the adhesive capability of air flow on the wheel rim 1 is directly enhanced, and the wind resistance is reduced when the wheel runs. A rim groove 102 is arranged between the rim walls 103, the rim groove 102 is in a U shape, a plurality of spoke connecting holes 107 are arranged at the bottom of the rim groove 102, and the spoke connecting holes 107 are used for facilitating connection of the wheel spokes 4 with the wheel rim 1.
As a preferred embodiment of the present application, more than one set of drag reducing generators 104 is provided on the outer side of the rim wall 103, the number of the drag reducing generators 104 is 16-18, as an alternative embodiment of the present application, when the number of the wheel spokes 4 is 24, the number of the drag reducing generators 104 is 18, when the number of the wheel spokes 4 is 20, the number of the drag reducing generators 104 is 16, and when the number of the wheel spokes 4 is 21, the number of the drag reducing generators 104 is 16, and the drag reducing generators 104 are used for increasing the attachment capability of the air flow and reducing the air resistance. Further, the drag reduction generators 104 are spirally arranged in an array in the circumferential direction of the rim wall 103.
The drag reduction generator 104 is fixed on the rim wall 103, the drag reduction generator 104 and the rim wall 103 are integrally formed, the integral strength of the drag reduction generator 104 is improved, the continuous playing effect is ensured, and optionally, the drag reduction generator 104 can be assembled on the rim wall 103 in a welding, bonding, embedding, screw locking and other modes, and the drag reduction effect can still be played. The drag reduction generators 104 have equal axial heights on the rim wall 103, alternatively, drag reduction generators 104 with unequal axial heights can also be present, wherein the drag reduction generators 104 with equal axial heights are periodically arranged, that is, the drag reduction generators 104 with equal axial heights repeatedly appear at fixed intervals, so that the outer side surface of the rim wall 103 presents a periodic undulating shape.
As a preferred embodiment of the present application, the drag reduction generator 104 includes a convex portion 105 and a concave portion 106, and the surfaces of the convex portion 105 and the concave portion 106 are in a cosine function curve shape, which satisfies the formula: y=acos [ ω (t-x/u) +Φ ]. Where A is the amplitude of the curve, ω is the angular frequency of the curve, t is the time of the curve, φ is the phase shift of the curve, and u is the wave number. Preferably, the convex portion 105 and the concave portion 106 are provided with continuous smooth transition, alternatively, the convex portion 105 and the concave portion 106 may be provided with no transition or discontinuous, and still play a role in reducing drag. The height difference between the protruding portion 105 and the recessed portion 106 is 0.5-2 mm, and as a preferred embodiment of the present application, the height difference between the protruding portion 105 and the recessed portion 106 is 1 mm.
The working principle of the bicycle wheel with the improved rim is as follows:
When a user rides the bicycle forward, the air and the bicycle wheel move relatively, so that the pressure of the air flow acts on the bicycle wheel, and according to the aerodynamics, the air pressure of the area with the faster flow speed is reduced, the air pressure of the area with the slower flow speed is increased, the area right in front of the bicycle wheel has the maximum air pressure, then the air rapidly flows over the side surface of the wheel rim 1 and reduces the air pressure, and then is separated from the wheel rim 1, a wake area is generated behind the bicycle wheel, the air pressure of the wake area is lower, a pressure difference is generated with the high-pressure area in front of the bicycle wheel, and resistance is generated for the movement of the bicycle.
When a user drives in an outdoor environment, natural wind is usually from all directions, not limited to the front. The air forms the contained angle with the wheel longitudinal plane for the direction of motion of bicycle wheel, produces the crosswind, produces the skew when crosswind can lead to the air current to leave the side surface of wheel rim 1, reduces the adhesive force for the air current breaks away from wheel rim 1 in advance, has increased the area in wake area by a wide margin, has reduced the air pressure in wake area and has further increased pressure differential, leads to the motion resistance of bicycle to increase.
The drag reduction generator 104 enhances the adhesive capacity of the air flow on the wheel rim 1, prolongs the time for the air flow to separate from the wheel rim 1, reduces the area of a wake flow area, reduces the pressure difference between the front and the rear of the bicycle wheel, and reduces the air resistance in the driving process.
As a feasible implementation mode of the application, the drag reduction generator 104 can adjust the height of the drag reduction generator 104 according to the functional requirement of a target scene, or change the height difference of the convex part 105 and the concave part 106, thereby realizing the purposes of changing the whole weight, balancing the production difficulty or adjusting the drag reduction effect, rapidly testing the product types meeting the requirements, and when the height and other parameters of the drag reduction generator 104 are adjusted, the actual wind resistance effect can be simulated through the computer CFD aerodynamics, and the working process is as follows:
An initial wheel rim 1 section is generated in which the side surface of the rim wall 103 is engaged with air during running, a boundary curve of the rim wall 103 is obtained, and the start point and the end point of the boundary curve are connected with a smooth curve, and the boundary curve and the smooth curve are collectively referred to as a curve C0. The starting point of the boundary curve is taken as a first point PNT 0-0, and the curve C 0 is uniformly divided into n equal parts, so that n intersection points PNT 0-1～PNT0-n are obtained.
The curve C 0 is shifted outward by a distance to obtain a curve C 0', and the reference point PNT is likewise taken 0'-0～PNT0'-n
The curve C 0 is shifted inward by a distance to obtain a curve C 0 ", and the reference point PNT is likewise taken 0"-0～PNT0"-n
The reference points are connected in a PNT0-0-PNT0'-1-PNT0-2-PNT0"-3-PNT0-4…PNT0-n-PNT0'-(n+1)-PNT0-(n+2)-PNT0"-(n+3)-PNT0-(n+4) cyclic manner to give curve W 0.
The reference plane is rotated by an angle about the hub central axis, curves C 1、C1' and C 1 "are established in the same manner, and the point set PNT 1-0~PNT1-n、PNT1'-0~PNT1'-n、PNT1"-0~PNT1"-n is obtained as such. Connecting the reference points according to a PNT1"-0-PNT1-1-PNT1'-2-PNT1-3-PNT1"-4……PNT1"-n-PNT1-(n+1)-PNT1'-(n+2)-PNT1-(n+3)-PNT1"-(n+4) circulation mode to obtain a curve W 1, obtaining a plurality of curves W 0～Wn according to the same method, connecting the plurality of curves as contour lines to form a curved surface, wherein the reference point PNT 0-0 of the curve W 0 is connected with the reference point PNT 1-1 of the curve W 1, the reference point PNT 2_2 of the curve 2, the reference point PNT 3_3 … … of the curve 3 until the reference point PNT n-n of the curve W n, and so on, the reference point PNT 0'-1 of the curve W 0 is connected with the reference point PNT 1'-2 of the curve W 1, the reference point PNT 2'-3 … … of the curve W 2 until the reference point PNT n'-(n+1) of the curve W n, and so on, and connecting the reference points on the curve W 0~Wn until all the reference points are connected in a one-to-one correspondence.
Thus, a curved surface shape is obtained which presents in appearance a plurality of projections and depressions which are spirally spread toward the outer edge, and which, when the rim is rotated, presents a wall surface traveling wave fluctuation state similar to that described above with respect to the horizontal plane direction section of the rim, thereby exerting the same effect as the above-described operation of reducing the wall surface air flow drop by generating the traveling wave fluctuation behavior in the wall surface. The obtained curved surface shape is split into a left half and a right half along the axial middle surface of the rim, one half is removed, and the other half is mirror-image copied, so that a curved surface with left and right mirror symmetry is obtained. The curved surface is the required final rim curved surface shape.
The rim curvature obtained in the above manner can be subjected to aerodynamic simulation analysis (CFD) with the original rotationally symmetrical rim shape, and the results are presented in the following table:
As can be seen from the analysis results, the curved shape generated in the above manner produces a significant drag reduction effect when faced with an incoming flow of 10-20 degrees, as compared to the original rim shape. The specific density, height difference, spiral angle and the like of the spiral protrusions and depressions of the curved surface can be adjusted by adjusting the parameters such as the shape, circumferential width, axial width, offset of the curves C 'and C' relative to the curve C, density of reference points, included angles between reference planes where the curves C are located and the like, so that various curved surface shapes can be obtained. Generally, comparing curved surface shapes generated by various parameters can obtain curved surface shapes with better drag reduction effect, or curved surface shapes with different characteristics can be obtained, for example, drag reduction can be performed under larger or smaller incoming flow angles, or production is facilitated, or light products are manufactured.
The present invention is not limited to the preferred embodiments, and any modifications, equivalent variations and modifications made to the above embodiments according to the technical principles of the present invention are within the scope of the technical proposal of the present invention.
According to the present invention, a bicycle wheel rim includes a tire-engaging portion located at an outermost rim of the wheel, a spoke-engaging portion located radially innermost of the hub and engaged with a wheel spoke, and a pair of radially extending air-engaging side surfaces located between the tire-engaging portion and the spoke-engaging portion. The air-engaging side surface has a series of concave-convex wave characteristics designed such that when the wheel is rotated, the rim side surface is brought into a state of wave motion according to wave equation y=acos [ ω (t-x/u) +Φ ] with respect to the direction of air flow, and such wave motion is effective to improve the adhesion of air flow on the rim side surface when the wheel is driven, thereby reducing the size of a turbulent flow region generated by the rim, and thus reducing aerodynamic resistance experienced by the wheel, according to some experimental results.
Air resistance (or aerodynamic resistance) is the force exerted by air on an object against the direction of object movement as the object moves in air. When the wheel is moving in air, the air flowing across the wheel surface has different rates and therefore different pressures throughout the wheel surface. Typically, the air exerts a maximum pressure at the foremost edge of the wheel, and then flows over the side surfaces of the wheel at an increased rate and reduced pressure, and at some point of separation, the air escapes from the side surfaces of the wheel and creates a turbulent region behind the wheel. This region is called the wake region, and the average pressure inside it is very low. The pressure differential between the high pressure region at the front of the wheel and the low pressure region at the rear of the wheel produces forces on the wheel opposite to the direction of motion, which is the primary source of bicycle wheel resistance.
In most practical riding environments, the direction of movement of the wheel relative to the air is not exactly opposite to the direction of movement of the wheel. Because of the varying degrees of natural wind in most outdoor environments, the direction of movement of the air relative to the wheel tends to form an angle with the longitudinal plane of the wheel, thereby shifting the position of the air flow away from the rim surface to one side. When this offset is increased to a certain extent, the adhesion of the air flow on the rim-side surface will be insufficient for the air flow to continue to flow against the rim-side surface, resulting in a great advance of the drop-off point of the air flow on the rim-side surface. At this time, the area of the wake area behind the wheel will increase substantially, resulting in a substantial increase in the differential pressure drag acting on the rim.
In some experiments and CFD (computational fluid dynamics) simulations, when the rim-side surface fluctuates in some fashion, the adhesion of the air flow to the rim surface can be increased, thereby significantly retarding the drop-off position of the air flow on the rim-side surface, which can result in a relatively low resistance for rims with larger angles of incidence or lower resistance for rims with no fluctuation shape of the side surface for the same angles of incidence.
The same aerodynamic principles can also be used on bicycle frames and rims, according to Amir m. Akbarzadeh of Texas a & M university and The Role of Amplitude on Controlling Flow Separation Using TRAVELING WAVE shaping of Iman Borazjani et al (study of paper sources ：The Role of Amplitude on Controlling Flow Separation Using Traveling Wave Morphing | AIAA SciTech Forum）, which shows that by creating undulations in the wing surface in a way that improves the airflow separation of the wing surface and thus the aerodynamic efficiency of the wing, and thus its lift:
In most bicycle riding environments, the direction of movement of the bicycle relative to the air is not exactly the same as the direction of movement of the bicycle relative to the ground. Because of the varying degrees of natural wind in most outdoor environments, air tends to form an angle with the longitudinal plane of the bicycle relative to the direction of movement of the bicycle. For an incoming flow that is angled with respect to the forward direction of the vehicle, the direction of flow is changed by the vehicle body or rim as it passes over the vehicle body or rim. Assuming that the forward direction of the vehicle is the Y axis, the direction perpendicular to the forward direction and parallel to the ground is the X axis, and the incoming flow velocity vector is V0, V0 can be split into an X-axis component V0X and a Y-axis component V0Y. The direction of the air flow is changed after the air flows through the wall surfaces of the vehicle body and the rim, and the Y-axis included angle becomes smaller, the air flow vector V0' at this time can be split into an X-axis component V0' X and a V0' Y, the air flow energy loss caused by the wall friction is ignored, the absolute value of V0' is equal to the absolute value of V0, and V0' Y is necessarily greater than V0Y, namely the speed of the air flow in the Y-axis direction is increased after the air flows through the wall surfaces, and the thrust force in the Y-axis positive direction is generated on the wall surfaces. This effect is commonly referred to as the sailboat effect, which is the principle that sailboat sails can generate forward thrust in upwind environments to keep advancing, and also the principle that bicycle frames and rims reduce drag by a specially shaped cross section in a specific airflow environment.
In practical situations, the wall surfaces of the bicycle frame and the rim cannot be completely free of resistance, but are limited by the adhesive force of air flow on the wall surfaces, and after the included angle of incoming flow is large to a certain extent, the air flow flowing through the wall surfaces can fall off from the wall surfaces, so that obvious differential pressure resistance is manufactured. How to make the wall surface of the bicycle frame and the rim capable of obviously reducing friction resistance and delaying the falling phenomenon of air flow as far as possible, thereby utilizing the drag reduction effect of the side wind as far as possible, is a main design subject of the bicycle frame and the rim.
The terminology used in the embodiments of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise, the "plurality" generally includes at least two.
It should be understood that the term "and/or" as used herein is merely one relationship describing the association of the associated objects, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.
It should be understood that although the terms first, second, third, etc. may be used in embodiments of the present application, these descriptions should not be limited to these terms. These terms are only used to distinguish one from another. For example, a first may also be referred to as a second, and similarly, a second may also be referred to as a first, without departing from the scope of embodiments of the application.
The words "if", as used herein, may be interpreted as "at … …" or "at … …" or "in response to a determination" or "in response to a detection", depending on the context. Similarly, the phrase "if determined" or "if detected (stated condition or event)" may be interpreted as "when determined" or "in response to determination" or "when detected (stated condition or event)" or "in response to detection (stated condition or event), depending on the context.
It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a product or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such product or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a commodity or device comprising such elements.
In particular, the symbols and/or numerals present in the description, if not marked in the description of the figures, are not numbered.
The bicycle wheel with the improved rim has the advantages of reducing production cost, improving wheel performance, being good in resistance reducing effect, being easy to adjust functional scenes and being low in research and development cost, the purpose of reducing resistance can be achieved by adopting a special wheel rim resistance reducing structure under the condition that new materials are not replaced, and the material cost of the new materials is saved. In addition, the drag reduction generator of the wheel rim can realize the purposes of changing the overall weight, balancing the production difficulty and adjusting the drag reduction effect by adjusting the height or changing the height difference of the protruding part and the recessed part, and can rapidly test the product type meeting the scene function requirement through the aerodynamic simulation parameter effect of a computer.
Claims (5)
1. The utility model provides a bicycle wheel of improvement rim, includes wheel rim (1), wheel tire (2), wheel hub (3) and wheel spoke (4), is equipped with wheel tire (2) on wheel rim (1), and the center of wheel rim (1) is provided with wheel hub (3), and wheel hub (3) are connected its characterized in that with wheel rim (1) through a plurality of wheel spoke (4): the wheel rim (1) is in a circular ring shape, the wheel rim (1) comprises rim grooves (102) and rim walls (103), the rim walls (103) are symmetrically arranged, the rim grooves (102) are arranged between the rim walls (103), more than one group of drag reduction generators (104) are arranged on the outer side surface of the rim walls (103) and used for increasing the attachment capacity of air flow and reducing air resistance, and the drag reduction generators (104) are in a spiral shape and are arranged in an array shape in the circumferential direction of the rim walls (103); the drag reduction generator (104) and the rim wall (103) are integrally formed, the drag reduction generator (104) comprises a convex part (105) and a concave part (106), and continuous smooth transition is arranged between the convex part (105) and the concave part (106); the number of the drag reduction generators (104) is 16-18 groups; the surfaces of the convex parts (105) and the concave parts (106) are in cosine function curve shapes;
Wherein an initial wheel rim section is generated in which a side surface of a rim wall is engaged with air during running, a boundary curve of the rim wall is obtained, a start point and an end point of the boundary curve are connected by a smooth curve, the boundary curve and the smooth curve are collectively referred to as a curve C0, the start point of the boundary curve is taken as a first point PNT 0-0, the curve C0 is uniformly divided into n equal divisions to obtain n intersecting points PNT 0-1～PNT0-n,
The curve C0 is shifted outward by a distance to obtain a curve C0', the reference point PNT 0'-0～PNT0'-n is also taken,
The curve C0 is shifted inward by a distance to obtain a curve C0", likewise taking the reference point PNT 0"-0～PNT0"-n,
The reference points are connected in a PNT0-0-PNT0'-1-PNT0-2-PNT0"-3-PNT0-4…PNT0-n-PNT0'-(n+1)-PNT0-(n+2)-PNT0"-(n+3)-PNT0-(n+4) cyclic manner to obtain a curve W0,
The reference plane is rotated around the central axis of the hub by an angle, curves C1, C1 'and C1' are established in the same way, a point set PNT 1-0～PNT1-n、PNT1'-0～PNT1'-n、PNT1"-0～PNT1"-n is obtained in the same way, reference points are connected in a cyclic way of PNT1"-0-PNT1-1-PNT1'-2-PNT1-3-PNT1"-4…PNT1"-n-PNT1-(n+1)-PNT1'-(n+2)-PNT1-(n+3)-PNT1"-(n+4) to obtain a curve W1, a plurality of curves W0-Wn are obtained in the same way, the curves are connected as contour lines to form a curved surface, wherein the reference point PNT 0-0 of the curve W0 is connected with the reference point PNT 1-1 of the curve W1, the reference point PNT 2_2 of the curve W2, the reference point PNT 3_3 … of the curve W3 is connected with the reference point PNT n-n of the curve Wn, the reference point PNT 0'-1 of the curve W0 is connected with the reference point PNT 1'-2 of the curve W1, the reference point PNT 2'-3 … of the curve W2 is connected with the reference point PNT n'-(n+1) of the curve Wn in a one-to-one correspondence manner, and a curved surface shape is obtained, and the curved surface shape is displayed in a convex shape and a concave shape extending towards the outer edge.
2. A rim improved bicycle wheel in accordance with claim 1 wherein: the drag reduction generators (104) are of equal axial height, or the drag reduction generators (104) of equal axial height are arranged periodically.
3. A rim improved bicycle wheel in accordance with claim 1 wherein: the height difference between the protruding part (105) and the recessed part (106) is 0.5-2 mm.
4. A rim improved bicycle wheel in accordance with claim 1 wherein: the rim wall (103) has a ring width of not less than 30 mm.
5. A rim improved bicycle wheel in accordance with claim 1 wherein: the rim groove (102) is U-shaped, and a plurality of spoke connecting holes (107) are formed in the bottom of the rim groove (102).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311444336.2A CN117301761B (en) | 2023-11-01 | Bicycle wheel with improved rim |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311444336.2A CN117301761B (en) | 2023-11-01 | Bicycle wheel with improved rim |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117301761A CN117301761A (en) | 2023-12-29 |
| CN117301761B true CN117301761B (en) | 2024-04-26 |
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| CN112744028A (en) * | 2020-12-31 | 2021-05-04 | 厦门佰业兴户外用品有限公司 | Bicycle rim with wind-breaking effect, bicycle wheel and bicycle |
| WO2022208106A1 (en) * | 2021-04-01 | 2022-10-06 | Drag2Zero Ltd | Bicycle wheel |
| CN218577408U (en) * | 2022-11-29 | 2023-03-07 | 厦门佰业兴户外用品有限公司 | Wind breaking rim, rim wheel set and bicycle |
| CN219446626U (en) * | 2023-02-06 | 2023-08-01 | 厦门市碳谷复材科技有限公司 | Flying wing wind-breaking rim, bicycle wheel and bicycle |
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5061013A (en) * | 1989-10-20 | 1991-10-29 | Hed Steven A | Bicycle rim and wheel |
| CN205768344U (en) * | 2016-07-01 | 2016-12-07 | 迪马斯（厦门）运动器材有限公司 | A kind of bicycle rim |
| CN109591570A (en) * | 2017-09-30 | 2019-04-09 | 比亚迪股份有限公司 | Hybrid electric drive system and vehicle |
| CN110525195A (en) * | 2019-09-26 | 2019-12-03 | 吉孚汽车技术(浙江)有限公司 | Power-driven system used for hybrid and its control method |
| CN112744028A (en) * | 2020-12-31 | 2021-05-04 | 厦门佰业兴户外用品有限公司 | Bicycle rim with wind-breaking effect, bicycle wheel and bicycle |
| WO2022208106A1 (en) * | 2021-04-01 | 2022-10-06 | Drag2Zero Ltd | Bicycle wheel |
| CN218577408U (en) * | 2022-11-29 | 2023-03-07 | 厦门佰业兴户外用品有限公司 | Wind breaking rim, rim wheel set and bicycle |
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Inventor after: Zhang Dongliang Inventor after: Zhang Yichi Inventor after: Yuan Jie Inventor before: Zhang Dongliang |
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